254 long's second expedition. 



of the venter is sometimes ferruginous, but it is always of a 

 deeper tint than that of [373] other parts of the body. It 

 seems to vary in size, I have a specimen less than one-fourth 

 smaller. 



4. A. fascipennis. — Black, slightly hairy ; wings varied with 

 blackish and hyaline. 



Inhabits Red river of Winnepeek. 



Body deep black, hairs sparse, very short, ferruginous ; head 

 with black short hairs above, and between, the antennae ; sides 

 of the mouth whitish ; hypostoma with dull, yellowish-ferruginous 

 hairs ; posterior orbits with silvery hair ; thorax with long hairs 

 before the wings ; scutel margined with piceous ; wings with a 

 wide, blackish-brown costal margin from which proceed two 

 oblique bands ; the basal one is dilated and attains the thinner 

 margin, on which it extends from the middle of the basal curve 

 of the wing to the extremity of the first and second nervures ; 

 the second band is irregularly arcuated and is abbreviated near 

 the thinner margin where it terminates in the form of a hook ; 

 on the costal margin near the tip is an oblique spot connected 

 with the costal colored margin; poisers fuscous; capitulum 

 white at tip ; tergum with the second and third segments obso- 

 letely piceous each side ; venter whitish at base ; feet dusky ; 

 tibia pale. 



Length one-fourth of an inch. 



This species coincides with the third tribe in Weidemann's ar- 

 rangement of this genus. It is small, and the wings are prettily 

 variegated. The specimen I obtained is remarkably destitute of 

 hair. 



5. A. costata. — Black ; wings hyaline, with a black costal 

 margin, and small anastomosis in the middle. 



Inhabits North-west Territory. 



Body deep black, with very short, sparse, sericeous hairs ; 

 thorax with the lateral hairs longer and pale yellowish-rufous ; 

 wings hyaline, with a blackish costal margin bounded [ 374 ] by 

 the fourth nervure as far as the middle, where it is abruptly con- 

 tracted so as to be included by the first apical nervure for a 

 short distance, when it is gradually contracted so as to be in- 

 cluded by the two costal nervures ; anastomosis near the centre 



